Io Hvac Controls MD-3412-BM Rectangular Zone Damper 34x12 in

Product Description

The IO HVAC CONTROLS MD-3412-BM is a 34 x 12 inch rectangular two-position zone damper built for forced-air zoning applications in residential and light commercial HVAC systems. The unit ships with a Belimo three-wire actuator mounted on the bottom of the damper frame, providing reliable open/close control through a standard 24-volt zone control board signal. At 14.76 pounds, this is a full-size damper designed for main trunk or large branch duct runs where precise zone isolation is required. The two-position design simplifies wiring and control logic compared to modulating dampers, making it a straightforward field install for experienced HVAC technicians.

This damper is suited for rectangular sheet metal ductwork in ducted split systems, air handlers, and fan coil applications where zoning is used to manage comfort across multiple areas of a building. It is typically installed in horizontal or vertical duct runs as part of a multi-zone forced-air system. The bottom-mount actuator orientation is suited for installations where top or side access is restricted. Contractors working on new construction or retrofit zoning projects will find the unit compatible with standard zone control panels that output a 24-volt two-position signal.

Key Features

• 34 x 12 inch rectangular damper frame fits large trunk and branch duct runs
• Belimo three-wire actuator included and factory-mounted at the bottom of the frame
• Two-position operation simplifies integration with standard zone control boards
• Bottom-mount actuator configuration accommodates restricted-access duct installations
• Sturdy construction at 14.76 pounds supports long-term cycle durability in zoning applications

Compatibility

Designed as an OEM-style zone damper for rectangular ducted forced-air HVAC systems using two-position 24-volt zone control panels.

Installation Notes

Installation should be performed by a licensed HVAC technician familiar with forced-air zoning systems. Shut down and de-energize the air handling system before mounting the damper or connecting actuator wiring. The damper must be secured to the duct using sheet metal screws or a slip-fit collar appropriate for the duct gauge. Follow all applicable local mechanical codes and the zone control manufacturer wiring diagrams when connecting the three-wire actuator leads.